Modern electrical grid systems are based on electric utilities and interconnected networks that deliver one-way flow of electricity from suppliers to consumers. However, increasing demand for energy, depleting fossil-based resources and a changing climate are emerging as challenges to continued and uninterrupted supply of electric power from electric utilities. As green energy sources such as, for example, solar, wind and geothermal sources emerge as a source of energy generation at residential homes, modernized systems must allow energy from these small distributed energy sources to be supplied to the grid. Therefore, as today's grid architecture is transformed into a smart grid, two-way flow of electricity and two-way flow of information is needed.
To achieve this two-way flow of information, electric utilities have installed smart meters at residential homes. Smart meters record near-real time information on consumer electricity usage in the home. The recorded information is subsequently transmitted to utilities on a predetermined schedule as metered data via a communication network. Transmitted metered data (i.e., electricity usage data) for a home may offer a window into the lives of people inside the residence by revealing the occupants' daily schedules, current occupancy level, use of individual appliances or the like.
Recently, transmitted metered data has raised confidentiality issues with respect to protecting personal privacy and safeguarding proprietary information from unauthorized access. For example, metered data that is transmitted over a communication network may potentially be subject to interception or theft by unauthorized third parties or hackers. Malicious attacks by hackers, who may eavesdrop on these communication networks, can gain access to personal and/or proprietary information, for example, access to consumer usage information or customer confidential account information. Additionally, metered data may provide appliance usage patterns that can shed light on an occupant's behavior inside the home that may potentially compromise his privacy in the home.
Conventional methods to protect personal and/or confidential information have relied on cryptography. For example, the ZigBee® Smart Energy Profile (SEP) standard from the ZigBee® Alliance has been adapted in some home area networks. The ZigBee® SEP implementation uses a certificate for providing security of metered data that is transmitted from a smart meter. However, the ZigBee® SEP implementation is limited as it neither provides certificate revocation nor certificate renewal capability. Other methods to safeguard metered data or information may include Advanced Encryption Standards (AES), RSA or Elliptic Curve cryptography, which are computationally intensive. Attackers could still glean usage patterns over encrypted data in transit and where they have physical access to the Smart Meters, they could gain encryption keys and see the usage data. Additionally, detailed personal usage information is available to the electric utility from which occupants' behaviors in the home through the persons' energy consumption could be derived. A system and method for ensuring confidentiality of metered data on a device and transmitted from a smart meter over a communication network would be desirable.